Steempeak has switched the notification system to one developed by @roadscape who works for Steemit INC. It does indeed require a json transaction to state when the last time you read your notifications... thus letting you in a sense clear your notifications.
This new notification system has some awesome benefits such as and most prominently missing in our previous system... MENTIONS.
Your answer is fine. It is a good explanation about the how. However, the 'why' doesn't seem to justify it, at least to me.